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A268772 Number of nX6 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once. 1
240, 620, 5214, 46312, 387146, 3104544, 24222418, 185142872, 1393319226, 10357051740, 76224579034, 556383657268, 4033179662378, 29064236056520, 208382539816438, 1487439977791192, 10576114792480666, 74940142727337224 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A268774.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 6*a(n-1) +51*a(n-2) -214*a(n-3) -1074*a(n-4) +2018*a(n-5) +7713*a(n-6) -10572*a(n-7) -22926*a(n-8) +30116*a(n-9) +25283*a(n-10) -32400*a(n-11) -15148*a(n-12) +15184*a(n-13) +5660*a(n-14) -2688*a(n-15) -1024*a(n-16) for n>18

EXAMPLE

Some solutions for n=4

..1..0..0..1..1..0. .2..2..2..1..2..1. .0..0..0..1..0..0. .1..2..2..2..2..1

..0..0..0..0..0..0. .2..2..2..2..2..2. .1..1..0..0..0..0. .2..1..2..2..2..2

..0..0..0..0..0..1. .1..2..2..1..2..1. .0..0..0..0..0..0. .2..2..2..2..2..2

..0..0..1..0..0..0. .2..2..2..2..2..1. .1..0..0..1..0..0. .1..2..1..2..2..2

CROSSREFS

Cf. A268774.

Sequence in context: A070123 A119659 A263161 * A202196 A060663 A092000

Adjacent sequences:  A268769 A268770 A268771 * A268773 A268774 A268775

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 13 2016

STATUS

approved

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Last modified January 20 11:01 EST 2020. Contains 331082 sequences. (Running on oeis4.)